Ratchet mechanism.



PATENTED MAR. 3, 1908.

R. C. ELLRIGH. RATCHET MEGHANISM.

APPLICATION FILED MAR. 9, 1906.

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UNITED sTATEs PATENT oEEioE.

ROBERT C. ELLRICII, OF SOUTI-IINGTON, CONNECTICUT, ASSIGNOR TO BECK, STOW & WILCOX COMPANY, OF SOUTHINGTON, CONNECTICUT, vA CORPORATION OF CONNECTICUT.

RATCHET MECHANISM.

Specification of Letters Patent.

Patented March 3, 1 908.

Application filed March 9. 1906. Serial No. 305.174.

To all whom 'it may concern:

Be it known that I, ROBERT C. ELLEICH, citizen of United States of America, residing at Southington, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Ratchet Mechanisms, of which the following is a specification.

The object of the invention is to produce a device of the class specified having features of novelty and advantage.

In the drawings--Figure l is a general side view showing my invention embodied in a bit-brace, parts being broken away to show the construction and arrangement of the mechanism. Fig. 2 is a sectional plan view on the line 2 2 of Fig. 3. Fig. 3 is in greater part a central vertical section of the part of the device in which the invention is embodied, the view being taken at right angles to Fig. 1. Fig. 4 is a sectional plan view on the line 4-4 of Fig. 3. Fig. 5 is a top view of the cam sleeve. Fig. 6 is a sectional view on the line 6--6 of Fig. 5 looking in the direction of the arrow.

Referring to the drawings c is the chuck, d the spindle, c the ratchet, d the hub of the sweep c fitting closely about the ratchet and slotted as at ff to take the pawls g g which are normally held in engagement with the ratchet by a band-spring h which preferably engages the pawls at a point about midway of their length.

Levers i L pivoted at 7c lr in the hub have engagement with each end of the pawls g g, their free ends projecting beyond the eXterior of the hub in the path of movement of the cams Z Z arranged interiorly of the sleeve m which is free to rotate about the hub, within limits, to disengage the pawls one at a time.

The chuck is secured to the sweep by the screw n. A spring detent o engages with notches p in the sleeve m which correspond to the three positions of the cams which operate the pawl levers.

By particular reference to Fig. 2 the pawls and one. of their operating levers are clearly seen, the lever being pivoted as at 7c with one end entering the ho es g in the pawls. There are two of these levers for each pawl, one at either side of the band-sp ring 7L, seen in Figs. 3 and 4. Fig. 3 shows the pawls and the holes g with which the levers engage.

The operation of the device will be readily understood. Figs. 2, 3 and 4 show one pawl withdrawn from engagement with the ratchet by the cams. Moving the sleeve m to the left until the s ring detent o engages the central notch p wil leaveboth pawls in engagement with the ratchet. Further movement to the left will withdraw the left hand pawl of Figs. 2, 3, and 4 from engagement with the ratchet andleave the right hand pawl of these iigures engaged. A lip m on the sleeve m opposite the cams Zhas a bearing on the swee hub to allow the proper rotation of the s eeve and this lip is so arranged that in connection with the ins r it forms a stop to limit the amount o` rotary movement of the sleeve, the limiting positions corresponding to the retracted positions ofthe pawls. By reference to Fig. 5 the top edge of the sleeve m is seen to be cut away to permit of the sleeve being passed down over the hub and over the levers t' and the ins r. The pawls of course are opposite y faced.

It is to be particularly noted that the pawls slide in and out in radial planes and that the edge of their engaging face is always parallel to the teeth of the ratchet; as a consequence of this construction it is seen that the entire length of the face of the pawl is in engagement with the ratchet tooth. This is a decided advantage over any rocking or pivoted pawl in which only a comparatively small part of their active faces engage with theratchet. My pawl is a sliding pawl as distinguished from the rocking or pivoted pawls andas shown in the'drawings there is a solid contact of about three-fourths of an inch between the pawls and the ratchet and the mechanism is as compact as the mechanism of any of the rocking or pivoted awls. The levers for each pawl are supporte on a common pivot and are arranged at the proper distance on each side of the band-spring to balance and cause the pawl to move freely and evenly.

I am aware that the details of my device are susceptible of alteration and modification and do not wish to be understood as limiting myself to the precise construction illustrated and described herein.

I claim as my invention:

1. A ratchet mechanism includin a driving and a driven member, one of said members having ratchet teeth extending lengthwise thereof, pawls carried by the other member, said pawls movable toward and away from said ratchet in radial planes, and a pivotally mounted lever in operative engagement with each pawl, and means for operating said lever.

2. A ratchet mechanism including a driven member having ratchet teeth extending lengthwise thereof and a driving member, pawls carried by the driving member and adapted to slide radially toward and from said ratchet, levers pivotally mounted upon the driving member and operatively engaging said pawls, and a sleeve surrounding said parts and having a cam to operate said levers.

3. ln a ratchet mechanism for screwdrivers, bit-braces, and similar tools, comprising the driving and driven member, a ratchet on the driven member, a hub on the driving member chambered to fit about said ratchet and having opposite radial slots, pawls located in said slots and adapted to slide towards and away from said ratchet, levers pivoted in said hub with one end in engagement with said pawls and the opposite end projecting beyond the periphery of said hub, springs normally holding said pawls in engagement with the ratchet, and a sleeve surrounding said hub and rotatable with res ect thereto, and cams on the interior of said s eeve adapted to coperate with the projecting ends of said levers to slide said pawls to disengage them one at a time from said. ratchet.

4. In a ratchet mechanism for screwdrivers, bit-braces, and similar tools, comprising the driving and driven members, a

ratchet on the driven member, a chambered hub on the driving member `fitting about said ratchet and having opposite radial slots, pawls mounted in said slots free to slide radially towards and away from said ratchet, a spring engaging said pawls midway between their ends and normally holding them in engagement with the ratchet, a pair of levers for each pawl pivoted in said hub, with one end in engagement with said pawl, said levers being located at equal distances on eitherside of said spring with their free ends projecting beyond the periphery of the hub, and means for engaging the irojecting ends of said levers to slide the pawls one at a time out of engagement with said ratchet.

5. A driving member and a driven member, one having ratchet teeth extending lengthwise thereof and the other carrying pawls, the pawls adapted to slide radially toward and from said ratchet, pivotally mounted levers engagingeach end of their respective pawls, and means to simultaneously actuate said levers to operate said pawls.

6. A ratchet mechanism including a driving and a driven member one of said parts having ratchet teeth extending lengthwise thereof and the other carrying pawls, the pawls movable radially toward and from said ratchet, a pivoted lever engaging each of said pawls, and means for actuating the levers to operate the pawls.

7.y A ratchet mechanism driven member having teeth extending lengthwise thereof, a driving member surrounding said driven member and having pawls, the pawls borne by the driving member and movable toward and from said ratchet, levers pivoted on the driving member and engaging each end of eachpawl, and a sleeve surrounding the driving member and having cams to simultaneously operate the levers in engagement with each pawl.

ln testimony whereof l affix my signature in presence of two witnesses.

ROBERT C. ELLRICH.

Witnesses THOMAS FWELCH, EDWIN G. LEwrs.

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